The conventional oil-fried cooking often uses a manual type apparatus. A pan with a round bottom is used for loading and heating oil, and then food together with spices are put into the pan for frying and removing manually. How many times that oil-fried food is turned over and how long the food is fried entirely depends on the experience and skill of the cook. Hence, it is difficult to control the quality of oil-fried food. In addition, oil-fried food together with spices must be filled, turned over and removed manually each time so that the cooker is too busy to maintain quality control when a large quantity of food is being oil fried simultaneously. Besides, a cook's skills and working speed are limited so that it is difficult to make a great quantity of oil-fried food in exactly the same quality.